But I guess as much as your ex missus wanted a Golf, would she have got an 'expensive' Golf lease deal? Everyone wants to get a good deal or drive something they thought they might not be able to drive.
She could have had a 5dr DSG 'R' or one of those cheap M135i deals that were doing the rounds, both for £20-£30 more per month. Or a Lean 5Dr manual (with equivalent engine) for £30-40 a month less. Both no brainers in my book when comparing... but she wanted a manual, 5 door petrol Golf, so that's what she got. It was cheap on paper, but compared to the market it was avg/expensive.
The Golf, no matter what model or how many toys have been chucked at it, isn't a £50k car. No-one would think it is so doesn't matter how loaded the person is, the price is an issue. You want a new/almost new Golf R, you get one for £35-£40k. If you are spending £50k, you either want more performance or a more premium car.
To you maybe, but to others probably not. Your own subjectiveness doesn't make the Golf not worth £50k, because it's exactly that, subjective. Ones person's attitude to money is different to the next persons. Exclusive paint on an Audi will cost you £2500-£3000, and some view that as madness, but plenty of people pay it.
As mentioned in this thread, a red fully loaded Golf R is a very rare thing, so if you were a cash buyer looking for something like that, you have found your car. True, the audience for that car is smaller, but there is an audience, that's my point.

Yes, that's why I put IMO at the end which you missed off your quote

Still, I would hazard a guess if you asked the motoring population, is the Golf a £50k car, I think you would find the answer would be no. Prices are creeping up and I'm sure £45k + Golfs will be more commonplace later in the year or 2021 when the Mk8 R arrives.
Audi exclusive paint is cheap by Lamborghini standards. A friend spec'd their Aventador SV in Verde Scandal which I think was an £11k option.